(ShareCast News) - Regulated rail fares in England, Scotland and Wales are due to increase by 1.9% from January 2017 based on official retail price inflation increases announced on Tuesday.After the Office for National Statistics showed the retail price index (RPI) rose 1.9% in July, up from 1.7% in June, this increase will be applied to regulated train fares, which represent around half of UK journeys.Tickets that are covered by regulated fares include saver returns, standard returns, off-peak tickets and season tickets, and represent around a third of revenues for train companies.The government has pledged that regulated fares will rise by no more than RPI for the rest of this Parliament.Train fares have risen by 25% in the past six years, far in excess of average weekly earnings, which have grown by 12%, according to analysis by the TUC and the Action for Rail campaign shows.While the government caps the rise in regulated fares to RPI, train companies can lift unregulated fares, such as off-peak leisure tickets, by as much as they choose.